The present invention is directed to a method and circuit arrangement for the transmission of message packets according to the asynchronous transfer mode (ATH) during the course of virtual connections over at least one ATM switching equipment or an ATH cross-connector in a communication network having a plurality of subscribers.
Communication in public, as well as, in private networks must provide an uninterrupted undisturbed transmission of message packets according to the asynchronous transfer mode (ATM) between the subscribers. High demands are made of the availability of the connections in the entire ATM communication network, particularly when exchanging data. This is true, for example, for the subscribers of a broad band communication network, for example the broad band ISDN (Integrated Services Digital Network), having data applications in the commercial field such as, for example, when coupling a plurality of computer centers or internal data networks (Local Area Network, Metropolitan Area Network). Such applications are characterized by a high data rate of an individual ATM transmission line (for example, 150 Mbit/s), failure of which affects many subscribers.
In this context, European reference EP-A1 0 384 936 discloses an ATM switching equipment that is redundantly designed in order to insure a disturbance-free switching service for each of the virtual connections in that ATM communication network. Over and above this, there are stand-by circuit measures in ATM cross-connectors for the case wherein connections are briefly unavailable because of line outages or the like. For assuring a high availability of the connections, it is necessary that the subscribers themselves must switch between a used subscriber line and an additional stand-by subscriber line. An interruption-free connection between the subscribers of the data exchange is thus not possible.